<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><p>Attractive and repulsive forces acting in the slurry due to different ions absorbed on surface of fine particles, especially colloidal ones, strongly affect the flow behaviour of highly concentrated fine-grained slurries. The attractive forces between the fine-grained solid particles initiate the coagulation process, which gives rise to voluminous aggregates where a large amount of water is fixed. A modification of the physical-chemical environment of the slurry by addition of a peptizing agent produces repulsive forces between particles. They result in destruction of the aggregates, water originally fixed in the aggregates is liberated, the viscous friction can play a larger role in the slurry, which is liquefied. To prove these process three different kaolin-water mixtures were tested with an overpressure capillary viscometer, rotational viscometer, and experimental pipeline loop. The effect of two peptizing agents and their concentration was investigated. It was demonstrated that even very low concentration of peptizing agent results in a significant reduction in the apparent viscosity and in the yield stress.</p></abstract>

Attractive and repulsive forces acting in the slurry due to different ions absorbed on surface of fine particles, especially colloidal ones, strongly affect the flow behaviour of highly concentrated fine-grained slurries. The attractive forces between the fine-grained solid particles initiate the coagulation process, which gives rise to voluminous aggregates where a large amount of water is fixed. A modification of the physical-chemical environment of the slurry by addition of a peptizing agent produces repulsive forces between particles. They result in destruction of the aggregates, water originally fixed in the aggregates is liberated, the viscous friction can play a larger role in the slurry, which is liquefied. To prove these process three different kaolin-water mixtures were tested with an overpressure capillary viscometer, rotational viscometer, and experimental pipeline loop. The effect of two peptizing agents and their concentration was investigated. It was demonstrated that even very low concentration of peptizing agent results in a significant reduction in the apparent viscosity and in the yield stress.

Drag reduction of dense fine-grained slurries

Institute of Hydrodynamics, Academy of Sciences of the Czech Republic, v. v. i., Pod Patankou 30/5, 166 12 Prague 6, Czech Republic

Journal of Hydrology and Hydromechanics

{"article-title":"Drag reduction of dense fine-grained slurries"}

Attractive and repulsive forces acting in the slurry due to different ions absorbed on surface of fine particles, especially colloidal ones, strongly affect...

Drag reduction of dense fine-grained slurries

Publié en ligne: 08 déc. 2010

Pages: 261 - 270

DOI: https://doi.org/10.2478/v10098-010-0024-y

Mots clés
kaolinové suspenze, snižování tření, experimentální výzkum, peptizace, reologie suspenzí

This content is open access.

Drag reduction of dense fine-grained slurries

Publié en ligne: 08 déc. 2010

Pages: 261 - 270

DOI: https://doi.org/10.2478/v10098-010-0024-y

Mots cléskaolinové suspenze, snižování tření, experimentální výzkum, peptizace, reologie suspenzí

This content is open access.

Mots clés
kaolinové suspenze, snižování tření, experimentální výzkum, peptizace, reologie suspenzí